Configuration of sounding reference signals based on user equipment reporting

Abstract

In an aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided. The apparatus may be a UE configured to receive configuration information indicating at least one cover code from a base station. The apparatus may be further configured to transmit at least one SRS to which the at least one cover code is applied in an SRS resource of an SRS resource set that is based on the configuration information. Another apparatus of the disclosure may be a base station configured to transmit configuration information indicating at least one cover code to a UE. The other apparatus may be further configured to receive at least lone SRS to which the at least one cover code is applied in an SRS resource of an SRS resource set that is based on the configuration information.

1 : A method of wireless communication at a user equipment (ULE), comprising:
 reporting, to a base station, information indicating a set of channel properties of a wireless channel on which communication with the base station is configured, each of the set of channel properties being based on receiving a set of pilot signals from the base station; and   transmitting at least one sounding reference signal (SRS) in an SRS resource of an SRS resource set to the base station according to a configuration that is based on the information indicating the set of channel properties.   
     
     
         2 : The method of  claim 1 , further comprising:
 determining the information indicating the set of channel properties based on receiving the set of pilot signals from the base station; and   receiving the configuration from the base station based on the information indicating the set of channel properties.   
     
     
         3 : The method of  claim 2 , wherein the determining the information indicating the set of channel properties comprises:
 calculating at least two values for an antenna port based on receiving the set of pilot signals, a first value of the at least two values being based on measurement of at least one Doppler shift on the antenna port and a second value of the at least two values being based on measurement of a delay spread on the antenna port; and   quantizing each of the at least two values,   the information indicating the set of channel properties comprising each quantized value of the at least two values.   
     
     
         4 : The method of  claim 2 , wherein the information indicating the set of channel properties comprises at least one of a Doppler shift that is measured on at least one antenna port based on at least one of the set of pilot signals, a Doppler spread calculated using the at least one Doppler shift, or a delay spread that is measured on at least one antenna port based on at least one of the set of pilot signals. 
     
     
         5 : The method of  claim 1 , wherein the information indicating the set of channel properties comprises a recommendation for at least one of a cover code, a difference of cyclic shifts, a comb size, or a cover code size. 
     
     
         6 : The method of  claim 5 , wherein the cover code comprises at least one of a time-domain orthogonal cover code (OCC) or a frequency-domain domain OCC. 
     
     
         7 : The method of  claim 5 , further comprising:
 determining the recommendation based on a UE mobility status.   
     
     
         8 : A method of wireless communication at a base station, comprising:
 receiving, from a user equipment (UE), information indicating a set of channel properties of a wireless channel on which communication with the UE is configured, each of the set of channel properties being based on a set of pilot signals transmitted on the wireless channel; and   receiving at least one sounding reference signal (SRS) in an SRS resource of an SRS resource set from the UE according to a configuration that is based on the information indicating the set of channel properties.   
     
     
         9 : The method of  claim 8 , further comprising:
 configuring at least one SRS resource of the SRS resource set for the UE based on the information indicating the set of channel properties; and   transmitting the configuration indicating the configured at least one SRS resource of the SRS resource set to the UE.   
     
     
         10 : The method of  claim 9 , wherein the configuring the at least one SRS resource of the SRS resource set comprises:
 configuring a set of orthogonal resources for the at least one SRS resource on at least two antenna ports using a cover code.   
     
     
         11 : The method of  claim 8 , wherein the information indicating the set of channel properties comprises a recommendation by the UE for at least one of a cover code, a difference of cyclic shifts, a comb size, or a cover code size. 
     
     
         12 : The method of  claim 11 , wherein the cover code comprises at least one of a time-domain orthogonal cover code (OCC) or a frequency-domain domain OCC. 
     
     
         13 : The method of  claim 12 , further comprising:
 configuring the at least one of the time-domain OCC or the frequency-domain OCC for the at least one SRS resource on at least one antenna port.   
     
     
         14 : The method of  claim 11 , wherein the recommendation indicates at least one of a delay spread of the set of channel properties or a mobility status of the UE. 
     
     
         15 : The method of  claim 8 , wherein the information indicating the set of channel properties comprises at least one quantized value corresponding to at least one of a Doppler shift, a Doppler spread, or a delay spread. 
     
     
         16 : A method of wireless communication at a user equipment (UE), comprising:
 receiving configuration information indicating at least one cover code from a base station; and   transmitting at least one sounding reference signal (SRS) to which the at least one cover code is applied in an SRS resource of an SRS resource set that is based on the configuration information.   
     
     
         17 : The method of  claim 16 , wherein the at least one cover code comprises at least one of a time-domain orthogonal cover code (OCC) or a frequency-domain OCC. 
     
     
         18 : The method of  claim 17 , wherein the at least one cover code comprises both the time-domain OCC and the frequency-domain OCC. 
     
     
         19 : The method of  claim 16 , further comprising at least one of:
 applying, on at least one antenna port, at least one first cover code of the at least one cover code to the at least one SRS across at least two symbols on one subcarrier; or   applying, on the at least one antenna port, at least one second cover code of the at least one cover code to the at least one SRS across at least two subcarriers in one symbol.   
     
     
         20 : The method of  claim 16 , further comprising:
 transmitting information indicating at least one recommendation for the at least one cover code.   
     
     
         21 : The method of  claim 20 , wherein the at least one recommendation is based on a UE mobility status. 
     
     
         22 : The method of  claim 16 , wherein the at least one cover code comprises at least one discrete Fourier transform (DFT) code having a frequency-domain dimension and a time-domain dimension. 
     
     
         23 : The method of  claim 22 , wherein the at least one DFT code is based on oversampling by a first factor in the frequency domain and oversampling by a second factor in the time domain. 
     
     
         24 : The method of  claim 22 , wherein the at least one DFT code comprises at least two orthogonal DFT codes derived from a common basis. 
     
     
         25 : A method of wireless communication at a base station, comprising:
 transmitting configuration information indicating at least one cover code to a user equipment (UE); and   receiving at least one sounding reference signal (SRS) to which the at least one cover code is applied in an SRS resource of an SRS resource set that is based on the configuration information.   
     
     
         26 : The method of  claim 25 , wherein the at least one cover code comprises at least one of a time-domain orthogonal cover code (OCC) or a frequency-domain OCC. 
     
     
         27 : The method of  claim 26 , wherein the at least one cover code comprises both the time-domain OCC and the frequency-domain OCC. 
     
     
         28 : The method of  claim 25 , wherein the configuration information indicates:
 a first cover code of the at least one cover code to be applied to the at least one SRS for transmission on an antenna port across at least two symbols on one subcarrier, and   a second cover code of the at least one cover code to be applied to the at least one SRS for the transmission on the antenna port across at least two subcarriers in one symbol.   
     
     
         29 : The method of  claim 25 , further comprising:
 receiving, from the UE, information indicating at least one recommendation for the at least one cover code, the at least one cover code being based on the at least one recommendation.   
     
     
         30 : The method of  claim 29 , wherein the at least one recommendation is based on a UE mobility status. 
     
     
         31 : The method of  claim 25 , wherein the at least one cover code comprises at least one discrete Fourier transform (DFT) code having a frequency-domain dimension and a time-domain dimension. 
     
     
         32 : The method of  claim 31 , wherein the at least one DFT code is based on oversampling by a first factor in the frequency domain and oversampling by a second factor in the time domain. 
     
     
         33 : The method of  claim 31 , wherein the at least one DFT code comprises at least two orthogonal DFT codes derived from a common basis. 
     
     
         34 - 134 . (canceled)